In a known vehicle lighting device, electrodes are attached to a cover (a lighting lens) which covers a light source (a bulb). The electrodes are for detecting a capacitance. A variation in capacitance caused by an occupant of a vehicle when the occupant touches a surface of the cover is detected. The light source is controlled to turn on when the variation in capacitance is detected. Namely, the electrodes are included in a touch switch.
To attach such electrodes to the cover, a sheet including the electrodes may be attached to the back surface of the cover (a surface on a light source side) with an adhesive. In this case, the back surface of the cover needs to be flat.
This is because an adhesive force between the cover and the sheet is low if the back surface of the cover is not flat. Therefore, the attachment of the sheet to the cover is difficult. Furthermore, if the back surface of the cover is not flat, air is more likely to enter between the sheet and the back surface of the cover. As a result, the capacitance varies from region to region according to whether the region contains the air. Namely, the sensitivity of the touch switch is different from area to area. Therefore, the attachment of the electrodes to the cover is difficult if the back surface of the cover is not flat.
The cover described above may include a first electrode and a second electrode. The first electrode is a component of the touch switch and the second electrode is an electrode for absorbing electric noises. With the electrodes, the stability in operation of the touch switch can be improved.
The sheet including the first electrode and the second electrode may be attached to a surface of the cover with an adhesive.
A typical example of such a cover to which the sheet is attached includes a main wall portion and a peripheral wall portion. The main wall portion includes a main surface (a surface on a vehicle interior side) of the cover. The peripheral wall portion includes a side surface of the cover. The sheet may be attached to main wall portion. With this configuration, an occupant of the vehicle can turn on a light source by touching the main surface of the cover.
However, if two kinds of the electrodes (the first and the second electrodes) are arranged in the main wall portion, the electrodes may be seen as a pattern. If so, the main surface looks messy, that is, the quality in appearance may decrease.
The larger the area of the first electrode, which is for detecting capacitances, the higher the operability of the touch switch. If the first electrode and the second electrode are arranged in the main wall portion, the area of the first electrode needs to be reduced by the area of the second electrode. The reduction in the area of the first electrode is a problem to be solved.